<!DOCTYPE html>

<head>
    <title>Hello World</title>
    <h1>Hello World</h1>
    <p>This is a simple HTML document</p>
</head>

<body style="background-color:blue;">
    <div style="background-color: aqua;">
        <h1>Hello World</h1>
        <p>This is a simple <b>HTML </b>document</p>
        <a href="https://cn.bing.com">This is a link to bing.com</a>
    </div>

    <address>
        Written by <a href="mailto:745727212@qq.com"> Goldfish</a>
    </address>
</body>